It recently emerged that a McDonald’s franchisee in the Lincolnshire area had banned all Scottish notes at his stores.

Mr Polonus was enjoying a break in London when he visited Starbucks in Great Marlborough Street, Soho.

He said: “I tried to pay for coffee and the manager refused to accept Scottish pounds insisting they are old and out of circulation.

“I was forced to pay by card. I was in a rush but in other circumstances I would have probably called the police.

“When I was attempting to pay, the member of staff pulled out a whole laminated poster with some notes they are not allowed to accept. Therefore it appears to me that the policy is backed by Starbucks HQ.”

The London Starbucks where the incident is alleged to have taken place

He added: “I am properly outraged by this. As a hard working immigrant living in Scotland, I had just collected my pay and was going to have fun in the UK capital city, London.

“You then learn the money you earn, which you got from the ATM where you live, turns out to be worthless.”

Mr Polonus said his Scottish banknotes resulted in two other incidents while on the same trip.

He continued: “I paid for a taxi with a Scottish tenner and the driver only accepted it because he had no choice as I had no notes other than Scottish ones.

“I was also buying food at McDonald’s at Liverpool Street Station and I had to make an effort to convince the person at the counter that my money is legal tender.

“It just takes the joy of unrestricted domestic travel away and makes you feel inferior because you get paid with ‘second class currency’.”

A Starbucks spokeswoman said: “We are looking into this with the local team. We accept Scottish bank notes in all of our UK stores and apologise for this customer’s experience.

“We would like to invite this customer back into store for a free drink on us.”

In September, a franchisee who owns ten branches of McDonald’s in the Lincolnshire area told staff to refuse to take Scottish notes, blaming problems with counterfeit notes.

However, the decision was met with widespread criticism who accused the policy of being anti-Scottish” and felt staff should have been trained to spot fraudulent notes.